1. Technical Field
The present invention relates to an optical module, an electronic apparatus, and a spectroscopic camera.
2. Related Art
There is a known wavelength tunable interference filter in which a pair of reflection films facing each other are provided and the distance between the reflection films is changed to extract light of a predetermined wavelength from light under measurement (see JP-A-7-243963, for example).
The wavelength tunable interference filter (optical resonator) described in JP-A-7-243963 includes a first substrate and a second substrate facing each other, reflection films disposed on the respective substrates and facing each other with an inter-reflection-film gap therebetween, and electrodes disposed on the respective substrates and facing each other. Further, one of the substrates (e.g., the second substrate) or a movable substrate is provided with a diaphragm. In the thus configured wavelength tunable interference filter, when a voltage is applied between the electrodes, the diaphragm can deform the second substrate to adjust the inter-reflection-film gap.
In the wavelength tunable interference filter disclosed in JP-A-7-243963 described above, which has a diaphragm-based configuration, however, the parallelism between the reflection films deteriorates when the inter-reflection-film gap is controlled due to unevenness in the thickness of the diaphragm, undesirably resulting in degradation in resolution of the filter.